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Author Topic: The Time is Now...  (Read 4807 times)
NR9R
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Posts: 151




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« Reply #15 on: February 24, 2012, 01:17:01 PM »

I would not call the 450D or 7200 a modern DSP radio. You cannot put IF DSP in a radio for 1000 bucks or so today and make it worth a crap
...to get good IF DSP you need at least a 590, K3 or 7410 not a 450

For the original authors sake, I want to point out that I think you are comparing different receiver architectures that use DSP in one IF stage to define the passband.  What primarily makes up the performance difference, and cost, between the radios being compared is a "narrow" 1st IF filter before the DSP There are some differences in tone and filter shape when comparing an analog receiver/wide 1st IF filter to a DSP based receiver/wide IF filter but I think most people would prefer an IF-DSP system for the versatility it offers in both transmit and receive--even in a $1k radio. 
   
...would not recommend a 2000 because while it does a lot of things it does not do any of them well because the IF DSP technology is is based on is very primitive and VERY dated

The receiver of the TS-2000 does not top the charts in dynamic range and it has some quarks but I would not attribute any of these weaknesses to an outdated IF DSP, but rather to the cheap ceramic filters in other analog filter stages (it is a common mod to replace some with good crystal filters).  It really is a remarkably performing radio for everything it does though.  The stock receiver performance is sufficient for the average station using wire antenna's on HF and small yagis on VHF/UHF (where the antenna gain is not enough to fill the band with strong stations).

This is a whole separate topic but it is interesting how many posts there are related to not being able to notice the difference while switching between 1st IF filters in new radios.  Many have became sold that their receiver will melt without a narrow "roofing filter" but the truth is that very few stations really need the extra dynamic range they offer.
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W8JX
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Posts: 5492




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« Reply #16 on: February 24, 2012, 02:32:03 PM »

This is a whole separate topic but it is interesting how many posts there are related to not being able to notice the difference while switching between 1st IF filters in new radios.  Many have became sold that their receiver will melt without a narrow "roofing filter" but the truth is that very few stations really need the extra dynamic range they offer.

Do not recall anyone talking about it melting but did talk about the lack of skirt selectivity in cheap or very dated IF DSP designs. The devil is in the details. Rigs like 450 are quick to quote a bandpass at 6 db down but very vague or evasive with specs on band pass at 60 db down because it would pail compare to a good analog rig with xtal filters. The IF DSP performance is ultimately determined by the speed and power of the DSP CPU's used as well as filters. This costs money to do right and DSP processors available in the days of TS 2000 were very primitive compared to today. They could have used a lot better DSP  hardware in 2000 when it was built but then it would have cost a awful lot more then too. 
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W5DQ
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Posts: 1209


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« Reply #17 on: March 15, 2012, 11:58:31 AM »


If you want a radio that can truly "do it all" consider the Kenwood TS2000, Which also covers VHF and UHF, Plus can cross band repeat them all!   A really neat feature!
The TS2000 also sells in the 900 dollar range good used.


I am a hard core Kenwood guy but would not recommend a 2000 because while it does a lot of things it does not do any of them well because the IF DSP technology is is based on is very primitive and VERY dated.

A point of reference on the Kenwood TS-2000. I have the X model with 1.2Ghz and I basically have it for 6M and up for now and a standby rig in case my venerable old TS-940S dies (I too am getting close to upgrade time but still have to save a few more scheckels). One thing I have noticed about the TS-2000S/X is even though it is a more 'modern' radio than the TS-940S, the 940 hears things the 2000 doesn't even know are there. Same antennas, same environment, same everything except recievers. On 6M the TS2000 is great for my needs but I hope I never have to press it into full HF service as it is a dog there IMHO.

Gene W5DQ
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Gene W5DQ
Ridgecrest, CA - DM15dp
www.radioroom.org
W8GP
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Posts: 192




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« Reply #18 on: March 16, 2012, 06:44:27 AM »

The FT-950 is also a very capable radio that can be found for 1000.00. Don't be scared by the menus, the learning curve is actually fairly short.This radio will blow the doors off of anything in it's price range.Some people will bad mouth this radio ( and the '450 as well) and then go on and compare it to radios costing twice as much. I admit, it is a middle-of-the-road radio but it is a great value. Don't get too hung up on the published numbers, for the casual operator the ergonomics becomes much more important.I've had a lot of radios over the years, some better and some worse(in terms of receiver performance), but for sheer operating enjoyment this is my favorite.Realistically, most of the newer radios will be a major improvement over your '751 so it mostly comes down to personal preference.Good luck!
                                               73, Greg
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